Bulk yarn process and apparatus



Feb. 2, 1965 o. H. CLAUSSEN BULK mu PROCESS AND mums Filed July 19, 1960INVENI' OR OLE HAAKON CLAUSSEN ATTORNEY United States Patent 3,167,845BULK YARN PRQCESS AND APPARATUS Ole Haakon Claussen, Wilmington, Del,assignor to E. l. du Pont de Nernours and Company, Wilmington, Etch, acorporation of Delaware Filed July 19, 196i), Ser. No. 43,891 14 Claims.(Cl. 28-41) This invention relates to a process and apparatus forproducing crimped fibrous structures, and more particularly to means forproducing relaxed fibrous structures having two different types of crimpsuperimposed upon each other.

Many recent improvements have been made in the field of crimping andbulking continuous filamentary yarns, particularly using fluid jettechnology for accomplishing the bulking of the filaments within theyarn. These improvements have for the most part been limited to crimpingsingle feed yarns and, therefore, have been rather costly from aproduction point of view. Also, most of the fluid crimping methods andapparatus have resulted in crimped yarns which have a residualshrinkage, which usually has to be removed by subsequent treating steps.

It is an object of this invention to provide a novel process andapparatus for producing relaxed crimped fibrous structures. A furtherobject is to provide an economical process and apparatus for crimpingsynthetic fibrous structures at a high rate of production. Anotherobject is to provide a simple procedure for obtaining fibrous structureshaving a combination of two different types of crimp superimposed uponeach other. Other objects will appear hereinafter.

In accordance with this invention, synthetic organic thermoplasticfibers in the form of a strand, such as yarn or tow flattened into asheet, or other continuous fibrous structure, are crimped in a relaxedcondition on a surface by feeding the strand to a moving surface andconveying the strand on the surface, crimping the fibers on the surfaceby means of a stream of pl asticizing fluid directed against the fibers,separating the strand from the fluid, and setting the crimp in thestrand. Dependent upon the effect desired, this general procedure can becarried out in several ways which are not equivalent. A highly effectiveprocedure which produces a unique composite crimp is to forward thestrand at high speed in the stream of plasticizing fluid to the movingsurface so that the strand is struck in a plastic condition against thesurface. This deforms the fibers to produce a crimp configuration whichis particularly desirable for many applications and will be described inmore detail subsequently. When the fibers are crimped in a tensionlessstate without being struck against the surface, a readilydistinguishable simple form of crimp is obtained which is less desirablein general, although this is an effective relaxed-crimping process.

The strand can be converted to a plastic condition by the plasticizingfluid, in which case a compressible fluid (gas or vapor) heated to atleast about 300 F. is preferable. However, the plastic condition canalso be produced by a fluid which has a solvent or swelling action onthe fibrous material, e.g., a solution of a swelling agent in a volatileorganic liquid. If the strand is already in a plastic condition beforeit is acted on by the fluid, it is only necessary for the fluid to havesufficient plasticizing action to maintain the strand in a plastic condition until the fibers have been crimped. Thus the strand can bepreheated by passage over a heated surface or be fed directly from amelt-spinning operation in a heat-plasticized condition. The plasticcondition can be provided by residual solvent remaining after asolventspinning operation, e.g., green cellulose acetate.

"'ice After the fibers have been crimped they are separated from theplasticizing fluid to set the crimp. The fluid is dispersed by strikingagainst the surface. Surface irregularities assist in dispersing thefluid away from the fibers and can also improve the deformation offibers crimped thereon. Preferably a screen surface, or other foraminoussurface, is used which is permeable to pass fluid therethrough whileretaining the fibers thereon for removal. The surface can be in the formof a drum, endless belt or disk on which the strand is conveyed awayfrom the fluid stream after treatment. The fibers are crimped in arelaxed condition by moving this surface at a slower speed than thespeed at which the strand is conveyed thereto. A single drum rotating ata slower surface speed can be used, but the strand can be separatedquickly from the treating fluid by passing it through the nip betweentwo such surfaces. An especially effective crimping action is achievedby forwarding the strand in a stream of plasticizing fluid to strikejust prior to the nip formed by two surfaces moving together at a speedslower than the speed at which the strand is conveyed thereto, e.g., bycrimping adjacent to the nip between the revolving surfaces of twodrums, arranged so that the strand is separated from the treating fluidat the nip immediately after crimping. Preferably at least one of thesesurfaces is foraminous so that the fluid passes through after forwardingthe strand against the surface. Crimping in this manner makes possible amore desirable fiber deformation and a more rapid setting of the crimpin a relaxed condition by separation from crimping fluid. When thestrand is plasticized by heat, the process conditions can be controlledso that the crimp is set by cooling as the strand passes through thenip. However, the strand can be conveyed on one of the surfaces to allowmore time for cooling, or positive cooling can be provided, as bycooling the surface or directing a cooling fluid onto the strand as itemerges from the nip.

FIGURES 1, 2 and 3 of the drawings illustrate a specific embodiment ofapparatus for practicing the process of this invention in whichthermoplastic yarn is simultaneously conveyed forward at high speed andconverted to a plastic condition by means of a flowing fluid and isstruck against a surface to mechanically deform the yarn and dispersethe fluid, the yarn being thereafter set in the mechanically deformedstate by the reversion of the yarn to a non-plastic condition.

FIGURE 1 is a front elevation of an embodiment of the apparatus of thisinvention;

FIGURE 2 is a side view of the apparatus of FIG- URE 1;

FIGURE 3 is an enlarged perspective View of the jet shown in FIGURE 1;

FIGURE 4 illustrates schematically a typical configuration of the novelyarn produced in accordance with this invention.

Referring to FIGURE 1, continuous fibrous strand 1, which may be a yarn,yarn warp, tow, non-woven batt, or the like, passes between fluidorifices 2 and 2 and through nip 3 of rotating hollow rolls 4 and 4 towindup roll 5. Before entering nip 3, the yarn passes through turbulentfluid zone 6 formed by the simultaneous intersection with the strand ofstreams of plasticizing fluid issuing from fluid jets 2 and 2' directedtowards the nip to intersect with the strand at about equal angles ashort distance from the nip so that the strand is conveyed forward athigh speed and struck against the surfaces of the hollow rolls at thenip. The fluid is preferably heated to convert the strand to a plasticcondition, but when the strand is preplasticized it is maintained in aplastic condition by the fluid. The strand is crimped and the fluid isdispersed at the nip, the strand then quickly reverting to a non-plasticcondition. As shown, the crimped product 8 emerging from the nip issuificiently deplasticized to be wound up or handled'in any conventionalmanner. In the specific embodiment of FIGURE 1, fluid orifices 2 and 2are contained in a single jet device 7 which also serves as a yarnguide, but quite obviously the fluid jets may be used which are entirelyindependent of one another and any yarn guide suitable for directing thestrand into the focal region of the jets is satisfactory so long as theyarn passing through the turbulent zone of plasticizing fluid issubjected to sufficient force to provide the desired crimping action. Ingeneral, the jets should pro vide at least /2 sonic fluidvelocity andshould intersect the strand at a distance of less than about 3 inchesfrom the nip or other surface against which the strand is impinged.

As shown in FIGURE 2, a side view corresponding to FIGURE 1, theapparatus is suitable for treating a plurality of yarns simultaneously.The strand 1 may also be a tow in the form of a warp sheet. Jet orificesin the form of slots provide high velocity fluid streams of a width atleast as great as the width of the warp of yarn forming the strand 1.This view also shows screen surface 10 provided on nip-rolls 4 and 4'.The fluid is dispersed therethrough into the roll interior indicated ashollow portion 9. The jet device 7 of FIGURES '1 and 2 is more clearlyshown in the enlarged perspective view of FlGURE 3. The jet orifices 2and 2' are passageways of generally rectangular cross-section whichtaper to relatively narrow slits 13 and 13' to discharge flattenedstreams of fluid at high velocity. They are arranged on each side ofstrand passageway 12 with the axes making an angle a therewith in therange from about to 75 so that the fluid streams converge on the strandemerging from slot 14 of the guide passageway and forward the strand tostrike against screen surface 10.

In the above embodiment the fluid streams act on the strand afterleaving the jet device 7, where thestrand is unconfined and open to theatmosphere. This is particularly advantageous in the process of thepresent invention. The linear focal region shown for treatment of a warpwould, of course, be modified when crimping a single yarn ormonofilament. The jets can be arranged to provide a focal region whichis essentially a point. More than two jets arranged symmetrically aroundthe yarn or monofilament, or a circular type of orifice, can be used.However, a Wide variety of jet devices can also be used which providefor action of fluid on a strand within the device, provided that theycan be operated to convey the strand forward against the screen or othersurface at a sufficiently high velocity to produce crimping. Suchdevices are disclosed in U.S. Patents No. 2,783,609, No. 2,852,906 andNo. 2,869,967, and in Belgium Patents No. 581,303 and No. 573,230.

According to the preferred process of this invention,

there is provided a multifilament strand containing continuousfilaments, said strand having a sawtooth crimp and the individualfilaments in the strand possessing an additional crimp characterized bya random, three-dimensional, non-helical, curvilinear configuration. Inaddi tion, each individual filament has an additional crimpcharacterized by alternate S and Z twist sections throughout its length;having a random number of turns between twist reversals; having a randomcontinuously varying angle of twist along its length; having a randomnumber of twist reversals per inch; and having at least one 3 turn andat least one 2 turn per inch which have a twist angle averaging at least5 or a twist intensity (angle) equivalent to at least 20 turns per inch.FIGURE 4 is a schematic illustration of this crimp in which the sawtoothcrimp designated by the lines a, b, c and d is superimposed upon amultifilament strand in which the individual fibers x, y and z containnon-helical, curvilinear crimp as further defined hereinbelow.

For purposes of clarifying the operation of the present invention, V isdefined as the speed. of the feed strand, that is, the speed at which anuncrimped strand is advanced into turbulent zone 6, the focal point ofthe fluid jets; V is defined as the speed of the yarn as it leaves theturbulent zone; V is the speed of thecrimped yarn as it passes throughthe nip of rolls 4,4 and, if no slippage occurs between .the yarn andthe rolls, V is also the linear surface speed of these rolls; and V isthe speed of the yarn passing to the next operation, e.g., the speed atwhich it is wound on take-up roll 5.

If V is equal to or greaterthan V and both are less than V only arandom, three-dimensional, non-helical, curvilinear type of crimp is-imparted to the yarn. When operating in this way the yarn'is notmechanically deformed by striking the surface but the surface doescontribute to the effectiveness of the crimping process. For example,when the direction of yarn feed and the rotation of the rolls 4, 4 isreversed, so that the yarn passes through the nip before beingsubjectedto the fluid stream and is then pulled away, little or no crimpis produced although the apparatus can be used in this manner to stretchor draw fibrous structures.

If V V V there is produced a fibrous structure having an essentiallyplanar zigzag type of crimp superimposed upon' a random,three-dimensional, non-helical, curvilinear type of crimp.

In most instances the take-up, speed V will'be somewhat greater than theroll speed V by a convenient amount for smooth operation. Some planarzigzag crimp will be pulled out during the normal operation of theprocess. Thus, the real or effective overfeed for a particular yarn willdepend upon the relative speeds of V and V.,, which can be adjusted togive the desired amount and type of crimp.

In general,,V V V V are preferred conditions for producingthe novelproducts of this invention. For preparation of crimped fibrousstructures having high bulk, the processing. conditions are adjusted sothat V V is between 3 and 10, and V /V is between 1.5 and 5 (preferablybetween 2 and 4). For thev preparation of crimped fibrous structureshaving low bulk, processing conditions should be adjusted so that V /Vis between 1.1 and 1.5, and V /V is between 1.05 and. 1.4.

Using a constant overfeed, the ratio of the amounts of the two types ofcrimp that may be produced in a strand can be varied by adjusting thevelocity of the impinging fluid and the angle the fluid makes with thesaid yarn. The degree of planar zigzag type of crimp, e.g., number ofcrimps/inch, may be increased by increasing the overfeed of the strandor decreased by decreasing overfeed.

The process of this invention can be used to crimp and bulk any naturalor synthetic plasticizable filamentary material. Examples of suchfilamentary materials include polyamides, such as polysebacamide,polyhexamethylene adipamide, polyundecanoiamide, polycaproamide, andcopolyamides; polyesters and copolyesters, such as the condensationproducts of ethylene glycol with terephthalic acid (polyethyleneterephthalate) or 2,6- naphthalic acid (polyethylene 2,6-naphthalate),ethylene glycol with a /10 mixture of terephthalic/isophthalic acids,ethylene glycol with a 98/2 mixture of terephthalic/ 5-(sodiumsulfo)-isophthalic' acids, poly(diphenylolpropane carbonate),1,4-bis(hydroxymethyl) cyclohexane with terephthalic acid to includetrans/cis mixtures, and poly(diphenylolpropane isophthalate);acrylonitrile polymers, such as polyacrylonitrile and copolymers ofacrylonitrile with vinylidene chloride, vinyl chloride, methyl acrylate;or anyv of the comonomers listed in Jacobson U.S. Patent No. 2,436,926or Millhiser U.S. Patent No. 2,837,501; vinyl chloride and vinylidenechloride polymers and copolymers; polyurethanes, polyester amides,polyethylenes and polypropylenes (both linear and branched),polycarbonates; fluorinated ethylene polymers and copolymers such aspolytetrafluorethylene and polymonochlorotrifluoroethylene and cellulosederivatives, such as cellulose acetate and regenerated cellulose.

The process and apparatus described herein are useful for crimping andbulking many different forms of fibrous structures as well as changingthe crystallinity of these structures. For example, monofilaments,multi-filament yarns, tow, a sheet of warp ends, woven and knittedfabrics, and webs, batts, papers, and other non-woven fibrous structuresmay be processed which have suficient coherence and strength to betreated without being pulled apart, and the term strand as used hereinrefers to all of these. The yarn may be of textile denier or of heavierdenier for carpet, tire, or other industrial uses. In all cases, thefibrous structure to be treated herein must be sufiiciently strong sothat it is continuously self-supporting under the conditions ofoperation (will not pull apart or be disintegrated).

The foraminous surface used to receive a strand conveyed forward by thestream of plasticizing fluid will preferably be in the form of twoscreen surfaced hollow rolls. Two contiguous foraminous belts moving inthe same direction at the same speed and passing between the nip of aplurality of hollow rolls arranged in tandem may also be used in asimilar manner. When two rolls are used, they will normally be driven atthe same surface speed, although they may be of the same or differentdiameters. Instead of the opposing fluid streams originating outside therolls, stationary jets may be mounted inside but near the periphery oftwo screen-covered rolls having hollow stationary center shafts. Theforaminous surface may suitably be a metal screen preferably made ofstainless steel, but also may be made of plastic, glass, ceramic, orother material, or may be a perforated sheet, a perforated belt,parallel wires, or the like.

The turbulent fiuid used to treat the fibrous structures may be air,steam, or any other gas or vapor, i.e., a compressible fluid, which iscapable of plasticizing the filamentary fibrous structures. superheatedsteam is the preferred fluid in the present process since it is a cheapand convenient source of high pressure i1 id with plasticizing action onthe filamentary material.

The temperature of the fluid medium must be regulated so that thefilamentary material does not melt. However, when treating filamentsmade from fusible polymers, the most effective bulking and crimping isusually obtained when the temperature of the turbulent fluid is abovethe melting point of the fiber. In this instance, the speed of themoving fibrous structure should be great enough to prevent melting ofthe filaments sufficiently to cause loss of their fibrous nature.Normally, the foraminous surface is not independenly cooled butnevertheless acts as a cooling medium for the crimped fibrous structure.It may be desirable in some instances to independently cool the rollsurface and/ or the crimped fibrous structure at the point where thefibrous structure is separated from the roll surface. The fluid streamsdirected towards the moving fibrous structure from opposite sides mayissue from two or more separate points or planes, or annularly orelliptically, provided the angle a between each fluid stream and themoving fibrous structure is greater than 5 and less than 75 and thefluid is directed in a generally concurrent direction with the movingfibrous structure.

The present invention provides a crimped fibrous structure which isrelaxed and contains practically no residual shrinkage. The process maybe controlled to give either a single type of crimp, which is therandom, three-dimensional, non-helical, curvilinear crimp (described byBreen and Lauterbach in copending U.S. Serial No. 842,524 filedSeptember 25, 1959, and now abandoned), or a composite of two types ofcrimp superimposed upon each other; namely, a planar zigzag type ofcrimp superimposed on this random, three-dimensional, non-helical,curvilinear crimp. The present process and apparatus is cheaper thanknown crimping processes, allows a greater flexibility in producingalmost any desired crimp level, and allows a faster production ofcrimped products than 6. the prior methods of crimping which employedfixed reservoirs wherein the yarn and fluid, if one were used, weremechanically confined. The present process may be operated at leastfaster than prior methods for obtaining crimped synthetic filamentarymaterials at comparable crimp levels. in addition, the instant inventionmay be used to treat multi-ends of yarn or fabrics, with no widthlimitation, to give uniform crimping along the full width of the fibrousstructure being treated. Also, the present invention produces crimpedproducts which have greater uniformity of crimp and other physicalproperties than those produced in closed system jets, and requires lesscritical control during operation than prior closed, mechanicallyconfined areas of turbulence.

EXAMPLE 1 A strand consisting of six ends of of continuous filamentpolyhexamethylene adipamide yarn (102068 /2 Z twist) in the form of twosections of three ends each is fed through apparatus of the typeillustrated in FIG- URE 1. Each filament has an essentially trilobalcross section. The apparatus contains two planar slit jets and the fluidis steam. Each jet has an external aperture opening in the shape of aslit approximately 4 inch long and inch wide. These slit openings in thejets are positioned at a distance of approximately 1 /2 inches from thenip of two screen-covered rolls, and these slits are positioned at anangle of 40 to a plane passing vertically through the nip of the rollsand parallel to the axes of the two rolls. The distance between the twoslit openings is approximately A1, of an inch. The polyamide yarn is fedinto the passage between the two slit openings by feeding it into a tubepositioned vertically between the two jets, said tube being separatedinside by a wire in the middle of the tube. The yarn is fed in twosections of three ends each on either side of the wire inside the tube.The yarn is fed into the tube a speed of yards per minute (V The fluidwhich is fed to the two jets is superheated steam at 450 F. at apressure of 80 p.s.ig. Each of the two rolls is of aluminum having adiameter of 12 inches, and is positively driven by external means. Eachroll is covered with a stainless steel 30- mesh wire screen, and ishollow beneath the surface screen, except for the drive shaft, to permitexit of steam through the screen. Both screen-covered rolls are drivenat a speed of 20 yards per minute (V The take-up speed of the yarn atthe exit end of the nip is approximately 60 yards per minute (V and thisyarn is collected on a positively driven take-up roll.

The uncrimped feed yarn and the crimped product yarn resulting fromtreatment according to this invention (both before heat setting as wellas after setting at 215 F. in saturated steam for 5 minutes) aresubjected to several yarn characterization tests. The results of thesetests, shown in Table I, indicate that the physical properties of thebulky crimped yarn, having a random, three-dimensional non-helical,curvilinear crimp are superior to those of prior art bulked and/ orcrimped yarns. The crimped yarn product has a combination of two typesof crimps, namely, an essentially planar zigzag crimp superimposed on ayarn in which the individual filament possesses a random,three-dimensional, non-helical, curvilinear crimp. Therefore, the numberof crimps per inch reported for the yarn product in Table I is the sumof the planar and three-dimensional types of crimp. When the strand iscrimped at considerably higher speeds, under otherwise comparableconditions, similar results are obtained.

EXAMPLE 2 A strand consisting of 16 ends of continuous filamentpoly(ethylene terephthalate) yarn (l50430 twist) in the form of twosections of eight ends each is processed with the apparatus of Example1, using superheated steam at 400 F. and 80 p.s.i.g., the otherconditions being the same as in Example 1. The results are shown inTable H.

TABLE I ,YarnCriinp Elongation (Percent) Initial Tenacity Elonga ModulusToughness No. crimps Residual Denier (gmsl tien* (gm./ (gm.-cm. per inchShrinkage As Exercised Boiled-off denier) (Percent) denier at denier)(Percent) Collected 100% elong.)

Uncriniped feed yarn". 13.0 5. 06 31.2 40. 7 1.1 Crimped yarn (beforesetting) 102 76 70 14. 7 4. 65 62. 3 13. S 2.1 13.0 Crimped yarn (heatset) 132 95 110 16. 8 4. 30 59. 7 13. 9 1. 8 16. 0 0

TABLE II Uncrimped feed yarn... 4.14 5. 23 24. 6 80. 3 1.0 Crimped yarn(before setting) 4. es 4. 37 35. 4.3. 7 1. 1 1s. 5 0 Crimped yarn (heatset 5. 62 3. 28 50. 8 33.8 1.2 17.5 0

*The yam crimp elongation in percent (extended length of yarn with allcrimp removed) (original crnnped length) X100 Since many difle-rentembodiments of the invention may be made without departing from thespirit and scope thereof, it is to be understood that the invention isnot limited by the specific illustrations except to the extent definedin the following claims.

I claim:

1. The process for manufacture of a bulked fibrous strand whichcomprises feeding a strand of synthetic organic thermoplastic fibers toa turbulent stream of plasticizing fluid to crimp the fibers, forwardingthe crimped strand in plasticized condition at high speed in the streamof plasticizing fluid to a foraminous surface, moving the surface insubstantially the direction of strand travel at a slower speed than thespeed at which the strand is conveyed thereto to support the plasticizedstrand in relaxed condition, additionally crimping the relaxed strandsolely. by directing a stream of plasticizing fluid against the fibersto crimp the fibers on the surface, separating the strand from thefluid, and setting the crimp in the strand.

2. A process as defined in claim 1 in which the surface is foraminous todisperse fluid therethrough and retain the yarn on the surface.

3. A process as defined in claim 2 in which the surface forms a nip withanother surface, the surfaces bei-ng moved together at aspeed slowerthan the speed at which the yarn is conveyed thereto and arranged topass the yarn through the nip after treatment.

4. A process as defined in claim 1 in which the fluid is a heatedcompressible fluid.

5. A process as defined in claim 1 in which the fluid is at atemperature above about 300 F.

6. A process as defined in claim 1 in which the fluid contains aswelling agent for the yarn.

7. A process as defined in claim 1 in which the surface is formed byrevolving surfaces of two drums arranged to provide a nip through whichthe yarn is passed and at least one drum has a foraminous surface forseparation of fluid from the yarn.

8. A process as defined in claim 7 in which the strand is composed of apolyamide and the plasticizing fluid is steam.

9. A process as defined in claim 7 in which the strand is composed of apolyester having an aryl group in the repeating units and the fluid issteam.

10. A process for crimping a synthetic organic fibrous strand whichcomprises forwarding the strandin a plastic condition axially through azone of turbulence formed by the intersection of two jets of acompressible strand-' plasticizing fluid each having at least /2 sonicvelocity, the jets being positioned .on opposite sides of the strandwith each forming an angle of about 5 to about 75 with the strandposition upstream from said intersection, decreasing the forward speedof the strand within a distance of less than 3 inchesafter entering thezone of (original crimped length) turbulence by striking the strandagainst a foram inons surface moving at a slower speed to produce arelaxed crimp, conveying the strand away from the plasticizing fluidon-the surface, and then removing the strand from the surface.

11. A process as defined in. claim in which the strand is composed ofthermoplastic material, the compressible fluid is heated above about 300F. to plasticize the strand, and the strand is deplasticized by coolingbefore removal from the surface.

12. Apparatus comprising a pair of rotatable hollow nip-rolls havingforaminous surfaces, fluid jet means for directing a turbulent'stream ofcompressible fluid into the nip of said rolls to pass through saidsurfaces, strand feeding means for supplying a fibrous strand to theturbulent stream to be forwarded into and through saidnip of therolls,:and take-up means for removing the strand from the rolls afterpassage through the nip.

13. Apparatus comprising a pair of rotatable hollow nip-rolls havingforaminous surfaces, fluid jet means for passing a turbulent stream ofcompressible fluid into the nip of said rolls and through. saidsurfaces, said jet means comprising fluid jets positioned to directstreams of fluid toward the nip of said rolls so that the axes of thejet streams intersect a common tangent to the rolls which isperpendicular to the nip, the intersection being at a distance of lessthan 3 inches from the nip and at an angle of about 5 to about 75 withsaid tangent, strand feeding means for supplying a fibrous strandbetween said fiuid jets to be forwarded into and through; said nip ofthe rolls, and take-up means for removing the strand from the rollsafter passage through the nip.

14. Apparatus as defined in claim 13 in which each jet stream axisintersects said tangent at an angle of between and References Cited inthe file of this patent UNITED STATES PATENTS 588,812 Bessonette' Aug.24, 1897 2,313,630 Dockerty Mar. 9, 1943 2,435,891 Lodge Feb. 10, 19482,760,252 Shattuck. Aug-28, 1956 2,807,862 Griset Oct. 1, 1957 2,869,967Breen Jan. 20, 1959 2,874,443 Griset Feb--24, 1959 2,914,835 SlayterDec. 1, 1959 2,964,900 Hicks Dec. 20, 1960 3,005,251 Hallden et al.-Oct. 24, 1961 3,016,599 Perry Jan. 16, 1962 3,036,357 Cook et a1 May 29,1962 FOREIGN PATENTS- 1,225,587 France Feb. 15, 1960 (CorrespondingBritish, 861,108, Feb. 15, 1961)

1. THE PROCESS FOR MANUFACTURE OF A BULKED FIBROUS STRAND WHICH COMPRISES FEEDING A STRAND OF SYNTHETIC ORGANIC THERMOPLASTIC FIBERS TO A TURBULENT STREAM OF PLASTICIZING FLUID TO CRIMP THE FIBERS, FORWARDING THE CRIMPED STRAND IN PLASTICIZED CONDITION AT HIGH SPEED IN THE STREAM OF PLASTICIZING FLUID TO A FORAMINOUS SURFACE, MOVING THE SURFACE IN SUBSTANTIALLY THE DIRECTION OF STRAND TRAVEL AT A SLOWER SPEED THAN THE SPEED AT WHICH THE STRAND IS CONVEYED THERETO TO SUPPORT THE PLASTICIZED STRAND IN RELAXED CONDITION, ADDITIONALLY CRIMPING THE RELAXED STRAND SOLELY BY DIRECTING A STREAM OF PLASTICIZING FLUID AGAINST THE FIBERS TO CRIMP THE FIBERS ON THE SURFACE, SEPARATING THE STRAND FROM THE FLUID, AND SETTING THE CRIMP IN THE STRAND. 